Search Publications
Cluster and Double Star observations of dipolarization
Balogh, A.; Zhang, T. L.; Dandouras, I. +15 more
We studied two types of dipolarization events with different IMF conditions when Cluster and Double Star (TC-1) were located in the same local time sector: 7 August 2004, 18:00-24:00 UT, during a disturbed southward/northward IMF interval, and 14 August 2004, 21:00-24:00 UT, when the IMF was stably northward. Cluster observed dipolarization as wel…
Electron-scale sheets of whistlers close to the magnetopause
Lavraud, B.; André, M.; Stenberg, G. +6 more
Whistler emissions close to the magnetopause on the magnetospheric side are investigated using the four Cluster spacecraft. The waves are found to be generated in thin (electron-scale) sheets moving with the plasma drift velocity. A feature in the electron data coincides with the waves; hot magnetospheric electrons disappear for a few satellite sp…
Energetic particle fluxes in the exterior cusp and the high-latitude dayside magnetosphere: statistical results from the Cluster/RAPID instrument
Asikainen, T.; Mursula, K.
In this paper we study the fluxes of energetic protons (30 4000 keV) and electrons (20 400 keV) in the exterior cusp and in the adjacent high-latitude dayside plasma sheet (HLPS) with the Cluster/RAPID instrument. Using two sample orbits we demonstrate that the Cluster observations at high latitudes can be dramatically different because the satell…
A statistical study of intense electric fields at 4-7 RE geocentric distance using Cluster
Buchert, S.; Karlsson, T.; Marklund, G. +3 more
Intense high-latitude electric fields (>150 mV/m mapped to ionospheric altitude) at 4 7 RE geocentric distance have been investigated in a statistical study, using data from the Cluster satellites. The orbit of the Cluster satellites limits the data collection at these altitudes to high latitudes, including the poleward part of the a…
Statistical phase propagation and dispersion analysis of low frequency waves in the magnetosheath
Fränz, M.; Dandouras, I.; Glassmeier, K. -H. +3 more
We present the results of a statistical analysis of low-frequency fluctuations in the high latitude regions of the dayside magnetosheath using CLUSTER as a wave telescope. Magnetic field observations are used to determine wave propagation directions and wave numbers for selected frequencies. Using observations of the plasma flow velocity we correc…
Evidence of transverse magnetospheric field line oscillations as observed from Cluster and ground magnetometers
Balogh, A.; Wild, J. A.; Yeoman, T. K. +3 more
The dynamic spectrum of ULF waves from magnetic field data obtained by the elliptically orbiting Cluster satellites (with an apogee of 119000km, perigee of 19000km and the orbital period of 57h) have been prepared in the frequency range 0 to 120mHz when the satellite was near its perigee. The existence of field line oscillations, with increasing f…
Empirical reconstruction and long-duration tracking of the magnetospheric boundary in single- and multi-spacecraft contexts
Owen, C. J.; Roth, M.; Dunlop, M. W. +3 more
The magnetospheric boundary is always moving, making it difficult to establish its structure. This paper presents a novel method for tracking the motion of the boundary, based on in-situ observations of the plasma velocity and of one or more additional observables. This method allows the moving boundary to be followed for extended periods of time …
Cluster observations of bounday layer structure and a flux transfer event near the cusp
Balogh, A.; Fazakerley, A. N.; Kistler, L. M. +6 more
On the 25th January 2002 between 10:00 and 12:00 UT, the four Cluster spacecraft passed through the northern high-latitude cusp, the dayside magnetosphere and into the magnetosheath in a linear formation. In the magnetosphere the PEACE electron spectrometers on the four spacecraft all observed a series of transient bursts of magnetosheath-like pla…
A corrector for spacecraft calculated electron moments
Génot, V.; Fazakerley, A. N.; Schwartz, S. J. +3 more
We present the application of a numerical method to correct electron moments calculated on-board spacecraft from the effects of potential broadening and energy range truncation. Assuming a shape for the natural distribution of the ambient plasma and employing the scalar approximation, the on-board moments can be represented as non-linear integral …
Cluster observation of continuous reconnection at dayside magnetopause in the vicinity of cusp
Balogh, A.; Eastwood, J. P.; Lucek, E. A. +10 more
In this paper, we present a case study of continuous reconnection at the dayside magnetopause observed by the Cluster spacecraft. On 1 April 2003, the four Cluster spacecraft experienced multiple encounters with the Earth's dayside magnetopause under a fairly stable southwestward interplanetary magnetic field (IMF). Accelerated plasma flows, whose…